Fetal life is considered one of the critical (or sensitive) periods when an exposure may have lifelong effects. Increased adiposity in later life seems to occur at both ends of the birth weigh spectrum: generalized obesity with higher birth weight and increased visceral adiposity and its metabolic consequences at lower birth weights. Whether or not these phenotypes are detectable in exposed children and whether or not they have common biologic pathways is a focus of this proposal. The specific aims of this proposal are: Aim No. 1: To examine in parallel the long-term consequences of intrauterine exposure to excess nutrition (maternal diabetes) and under nutrition (growth restriction) on/childhood body size, fat patterning and markers of insulin resistance, among children of different ethnic groups. Aim No. 2. To explore hypothesis of intrauterine hormonal "programming" through which fetal exposures could increase the risk of obesity and insulin resistance in children. The proposed project is a prospective study proposing to enroll a total of 810 eight to eleven-year old offspring of diabetic pregnancies (exposed group-1), offspring of non-diabetic pregnancies with intrauterine growth restraint (exposed group-2), and control children (unexposed group), as well as their biological mothers, in three ethnic groups (non-Hispanic whites, Hispanics, and African-Americans). Comparison of exposed and unexposed groups will allow assessment and disentangling of the effects of exposure to diabetes mellitus in utero and intrauterine growth restraint on body size, fat patterning and insulin resistance markers and features later in childhood. The proposed research should also help understand whether these exposures have direct biological influences or are mediated through lifestyle choices. Such studies could ultimately lead to the development of strategies for early life prevention of future chronic disorders.